Combined rammer and cam means for chambering cartridges in revolver-type guns



ETAL 2,900,876 MEANS FOR CHAMBERING OLVER-TYPE suns 11, 1956 Aug. 25, 1959 J. G. BRUBAKER COMBINED RANMER AND CAM CARTRIDGES IN REV Filed Sept Fiji. 1

IN V EN TORS. John ELB ru'b aka? William E -RE U116. 51

11 Eugene 5-Wu.ss

BY m mw United States Patent F COMBINED RAMMER AND CAM MEANS FOR CHAMBERING CARTRIDGES IN REVOLVER- TYPE GUNS John G. Brubaker, Park Forest, Eugene S. Wassel, La

Grange, and William E. Reynolds, Riverside, Ill., assignors, by mesne' assignments, to the United States of America as represented by the Secretary of the Army Application September 11, 1956, Serial No. 609,331

7 1 Claim. (Cl. 89-455) Our invention pertains to an automatic gun provided with a drum for inclosing cartridges and more particularly to a cam-type cartridge positioner therefor.

In a revolver-type automatic gun, a drum including chambers for cartridges is rotated by a reciprocating actuator to convey the chambers to stations corresponding thereto including stations for first and second stage ramnung.

In a conventional gun, the cartridges are pressed part way into the drum and then fully chambered therein by fingers of a rammer secured to the actuator. The fingers are disposed for engagement with the cartridges in successive ramming stations.

The chambers and cartridges are tapered and the feeder is spaced from the drum. In the first stage of the ramming, each of the cartridges is projected to a position in the chamber with a portion of the cartridge projecting therefrom and the first stage ramming finger is carried rearwardly on the actuator during the succeeding reciprocation thereof, leaving the cartridge loosely disposed in the chamber.

It is an object of our invention to provide the recoil unit with a cam device to positively chamber the cartridges in the drum following the first stage ramming.

Another object of our invention is to provide the cam device with a latch for preventing the rearward displacement of the cartridges from the partial-ram position and for positioning the partially rammed cartridges for engagement by the cam device.

Other aims and objects of our invention will appear in the following explanation.

In carrying out our invention, the recoil unit is provided with a rammer for stripping the cartridges from the ammunition belt and conveying the cartridges to a partialram position partly projecting into the drum. A cam is disposed on the recoil unit for engagement with the bases of the cartridges while being carried from the first of the ramming stations to the firing station to chamber the cartridges in the drum responsive to rotation thereof. The cam is provided with a latch, pivoted to permit passage of the cartridges to the partial-ram position and springbiased to retain the cartridges therein. The latch limits rearward movement of the cartridges from the partial-ram positions and eliminates requirement for a round stop to retain the chambered cartridges in the drum.

For a more complete understanding, reference is directed to the following description and accompanying drawing in which: 7

Fig. l is an elevational view of the left side of a gun partly cut away incorporating our invention;

Fig. 2 is a view along line 22 of Fig. 1;

Fig. 3 is a view along line 3-3 of Fig. 1 with cartridges removed; and

Fig. 4 is a perspective view from the left front of the gun.

Accordingly, a gun 12 includes a receiver 14, a recoil unit 16, and a cartridge drum 18 with chambers 20 for cartridges 22. Drum 18 is disposed on recoil unit -16 to 2,900,876 Patented Aug. 25, 1959 of the ramming stations by a feeder 26 on receiver 14,

and a rammer 28 is disposed on actuator 24 to propel the cartridges from the engaging links 25 to a position partly extending into the chamber 20 in the first ramming station responsive to the reciprocation of actuator 24.

Disposed on recoil unit 16 is a cam device 30 which includes a cam surface 31 that leads from the first of the two ramming stations to the firing station. Cam surface 31 is disposed so as to be engageable by the bases of the cartridges 22 during subsequent rotation with drum 18 from the first of the ramming stations and is developed helically so as to convert the rotational travel of the cartridges with the drum to linear movement into the cooperating chambers 20 for full chambering therein while being rotated through the second of the ramming stations to the firing station.

A latch 32 is slidably mounted on cam device 30 so as to be cammingly moved to a depressed position by engagement of the cartridges 22 when moved to the partialram positions thereof by rammer 28 and is spring-biased to a normal position. When latch 32 is in the normal position the partially rammed cartridges are blocked thereby from rearward displacement and are positioned so as to be engageable with cam surface 31 when rotated past the first of the ramming stations to the firing station.

During the operation of gun 12, actuator 24 is reciprocated to rotate drum 18 so that the chambers 20 therein pass successively through the two ramming stations to the firing station wherein the chambered cartridges are discharged. When one of the chambers 20 is in the first of the ramming stations, rammer 28 on actuator 24 propels a cartridge from the engaging one of the links 25 part way into the aligned chamber to a partial-ram position. While being rammed forwardly the cartridge 22 engageably depresses latch 32 which, when the cartridge is in the partial-ram position, springs back to the normal position thereof to prevent rearward displacement of such cartridge and to position it for the subsequent engagement by cam surface 31. Thus, during the following two reciprocations of actuator 24, drum 18 is rotated to carry the cartridge from the first of the ramming stations to the firing station and while being rotated thereto the base of the cartridge is engaged by cam surface 31 to convert the rotational travel of the cartridge in drum 18 to linear forward movement so as to be fully chambered when indexed in the firing station.

Although a particular embodiment of the invention has been described in detail herein, it is evident that many variations may be devised within the spirit and scope thereof and the following claim is intended to include such variations.

We claim: a

In a gun fed with cartridges from a linked belt and including a receiver with a recoil unit therein, a drum rotatably disposed in the recoil unit and provided with cartridge chambers, and actuating means for serially rotating the drum and successively indexing the chambers in stations including a pair of adjacent ramming stations and an immediately succeeding firing station responsive to forces produced by discharge of the cartridges in the firing station, the combination of a rammer disposed on the actuator means for successively moving the cartridges from the linked belt to a partial-ram position in the chain bers when indexed in the first of the pair of ramming station's, and a cam device including a latch engageable by the bases of the cartridges in the partial-ram position to prevent displacement of the cartridges rearwardlytherefrom; a helical cam surface leading from the first of the ramming stations to the firing station,-said cam surface being disposed "for engagement by' the bases of the cartridges when rotated from the first of the ramming stations and being helically developed to cammingly convert' rotational movement of the cartridges with the drum to longitudinally displacement to a fully chambered posia o 4"" tion in the cooperatingb'nes of -the chambers when moved by the drum through the second of the ramming stations to the firing station.

FOREIGN PATENTS 1589, 155; ore-atsr'i ain'; s ar. 18, 1953 

